Well, I'm afraid to say that you didn't choose your configuration properly. I'd recommend you this, very recently built 3-Workstation class PCs based on Sandy Bridge processors:
Processor: Core i7-2600K (great OCing, no Vt-d) or 2600 (decent OC, with Vt-d). Both are quad-core, HT with 8 threads, more than enough for 99.9% of today's *enterprise* needs, let alone gaming, encoding blah blah.
Motherboards: Asus P8P67 WS Revolution (2600K), Gigabyte GA-P67A-UD7 (2600K) and Intel DP67BG Extreme series (2600; most importantly for Vt-d).
RAM: 16GB for each Workstation - 2 x 8GB kits each. 8GB kit - CMZ8GX3M2A1600C8.
Graphics cards: Sapphire 5870 DDR5 2GB Eyefinity 6 ed. (1 No) and Sapphire 5850 DDR5 2GB Toxic (2 Nos)
LCD: 12 Nos (6 + 3 + 3; Eyefinity config) - all 27", ViewSonic X Series VX2739WM (obviously, costs a lot but I need them).
PSU:Corsair CMPSU-750HX series, more than sufficient.
SSD: Sata-III based Crucial RealSSD C300 series - 128GB (1 No each for 3 machines)
HDD: WD Black, Sata 6Gb/s with 64MB cache, 2TB (6 Nos; 2 per machine).
Case: NZXT Phantom (1 White and 2 Black); rock solid product.
OSes: Linux (couple of distros) and Windows 7 Professional x64 ed. on Parallels 4.0 Desktop (Virtualization mode).
Those machines are running damn good in my business environment. Rock solid performance, superb Eyefinity experience (eliminates buying lot of PCs!) and best value for money compared to X58/Bloomfield platform for sure.
Note: Most of the Hardware bought from the US, baring components like LCDs, Cases etc. Point is, I don't know the prices in India for my config.
Based on my experience with Design, Modeling and Simulating (Pharma/Bio/IT industries), you don't need Qaudro 4000 cards (overkill) and Xeon Workstation. Well, instead of Dell Xeon Workstations, we use the latest Mac Pros (12 cores; for those expensive highly customized workstations, we chose 2xATI 5770 config per each WS. That's a lot!). My Research staff are very happy working with them, in fact they were shocked to see performance of the latest Hardware.
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You get 2 CDs, choose whatever you want. Only one.
Anyway, I would recommend you to go this way:
Install and use Windows XP Mode in Windows 7
That solution would be more useful, backward compatible too (legacy apps, if any).
BTW, how much memory installed on that machine?